Response of Several Genetic Sources of Corn to Acidic Soil¹

Abstract

Plants differ in their ability to take up nutrients. Developing genotypes efficient in utilizing nutrients from acid or low nutrient soils would aid in growing crops successfully when mineral supplementation is not feasible. This study was conducted in the greenhouse using mine spoil soil of initial pH 3.9 with variables of genetic sources of corn (Zea mays L.) and lime rates. Genetic source variability was more pronounced under stress conditions (low pH) than under nonstress conditions. The genetic sources PI270083, PI270080, and Va17 showed higher tolerance to acidic conditions than others. Inbred C105, highly susceptible to low pH, showed the most visual root damage as well as the lowest relative dry matter yield. Aluminum concentration in the plant tissue did not vary significantly with lime level; however, exchangeable Al in the soil decreased drastically as the level of lime application increased. Manganese in the plant tissue and in the soil (DTPA extractable) both decreased with increased lime rate. Dry matter yield decreased significantly at 16 500 kg ha−1 of lime compared with 8000 kg ha−1. Phosphorus concentration decreased in the plant as well as in the soil (Bray P‐1 extractable) at 16 500 kg ha−1 lime, which could have been a factor in reduced yield. Genetic source by lime interaction was significant for Ca, Mg, Al, and Mn concentration indicating that selection under different pH levels would be productive.

CHANGES OF pH AND AVAILABLE PHOSPHORUS AND CALCIUM IN RHIZOSPHERE OF ALUMINUM-TOLERANT MAIZE GERMPLASM FERTILIZED WITH PHOSPHATE ROCK

“…Two P levels were used: 0 and 400 mg kg Ϫ1 . Seven maize inbreds were used, six of them (4,5,7,11,15, and 17) from CIMMYT at Cali, Colombia, and ranked as aluminum-tolerant, were bred in a soil high in Al. The seventh inbred (76) was a local breeding obtained in a calcareous soil, in the maize program of CENIAP-FONAIAP (Table 1).…”

“…It has been reported a significant variability among maize genotypes in dry matter yield and in nutrient uptake (9,10,11). Differences in nutrient uptake among plant genotypes or plant species may be attributed, among other factors, to the rhizosphere effect which has been shown to increase the nutrient availability to plants (12,13,14).…”

Growth and Nutrient Composition of Maize Genotypes in Acid Nutrient Solutions

“…The influence of pH on plants has been investigated using soil or nutrient solution as the plant growth medium. Nutrient solutions are commonly preferred (Sherchan et al, 1983;Lutz et al, 1971;Siraj-Ali et al, 1987;Kim et al, 1985;Islam, 1980;, because there is less confounding of pH with pH-induced nutrient excesses or deficiencies.…”

Morphological alterations of corn (Zea mays L.) plants in response to aluminum toxicity in the soil

“…The negative effects on crop development and yield caused by the presence of toxic levels of Al in the soil were also reported by Olmos & Camargo (1976), and Foy (1983). Sherchan et al (1983), Mascarenhas et al (1984) and Lopes et al (1987) showed that corn seedling primary root length was the best toxic plants were the most sensitive parameters to asses the presence of Al in the soil. The presence of toxic aluminum in the soil reduced the development of the corn plants in the field for the stem diameter, height, leaf area, accumulation of aerial part dry matter, total and yield.…”

“…Studies by Lafever (1977), Camargo (1984), Mascarenhas et al (1984), Lopes et al (1987) and Llugany et al (1995) showed irregular growth in the root systems in Hordeum vulgare (L.), Oryza sativa (L.), Glycine max (L.) Merril and Zea mays (L.) when cultivated in acid soils. Sherchan et al (1983), Mascarenhas et al (1984) and Lopes et al (1987) showed that seedling primary root length was a better indicator to assess varietal tolerance to the increase in the aluminum concentration in the nutritive solution than the accumulation of dry matter of the aerial part and roots. The present experiment was carried out to identify the morphological parameters which best characterize the sensitivity of the corn crop and of corn genotypes to toxic aluminum in field soils.…”